• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.75-80
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• 2000

We revisit the arrested Ekman boundary layer problem, using a fully non-linear numerical model with the subgrid dissipation modeled by the large eddy simulation method (LES). The main objective of this study is to find out whether the dynamic balance of the arrested Ekman boundary layer explained by MacCready and Rhines (1991) is valid for high Reynolds number. The model solution indicates that for high Reynolds number and low Richardson number flows, the density anomaly diffusion by near-wall turbulent action may become intense enough to homogenize completely the density structure within the boundary layer, in the direction perpendicular to the sloping wall. Then the buoyancy effect becomes negligible allowing a near-equilibrium Ekman boundary layer flow to persist for a long period.

• International Journal of CAD/CAM
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• 제12권1호
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• pp.29-37
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• 2012

A new algorithm has been developed to construct surface from the contours having branches and the final smooth surface is obtained by the reversible Catmull-Clark subdivision. In branching, a particular layer has more than one contour that correspond with at least one contour at the adjacent layer. In the next step, three-dimensional composite curve is constructed from contours of a layer having correspondence with at least one contour at the adjacent layer by inserting points between them and joining the contours. The points are inserted in such a way that the geometric center of the contours should merge at the center of the contours at the adjacent layer. This process is repeated for all layers having branching problems. Polyhedra are constructed in the next step with the help of composite curves and the contours at adjacent layer. The required smooth surface is obtained in the proposed work by providing the level of smoothness.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.132-132
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• 2011

The sheet resistance (Rs) of undoped GaN films on AlN/c-plane sapphire substrate was investigated in which the AlN films were grown by R. F. magetron sputtering method. The Rs was strongly dependent on the AlN layer thickness and semi-insulating behavior was observed. To clarify the effect of crystalline property on Rs, the crystal structure of the GaN films has been studied using x-ray scattering and transmission electron microscopy. A compressive strain was introduced by the presence of AlN nucleation layer (NL) and was gradually relaxed as increasing AlN NL thickness. This relaxation produced more threading dislocations (TD) of edge-type. Moreover, the surface morphology of the GaN film was changed at thicker AlN layer condition, which was originated by the crossover from planar to island grains of AlN. Thus, rough surface might produce more dislocations. The edge and mixed dislocations propagating from the interface between the GaN film and the AlN buffer layer affected the electric resistance of GaN film.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1840-1842
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• 1997

MgO protection layer on the dielectric layer in PDP prevents a dielectric layer from sputtering and lowers the firing voltage due to a large $\gamma$-Coefficients. Until now, the MgO protection layer is mainly prepared by E-beam evaporation. However, there are some problems that is easy pollution and change of its characteristics with time and delamination. Therefore in this study. MgO protection layer is prepared on dielectric layer by R.F. magnetron sputtering with Mg target under various conditions. The sputtered MgO shows the better discharge characteristics compared with MgO deposited by E-beam evaporatior.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.958-961
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• 2007

The electrical characteristics of organic thin-filmtransistor (OTFTs) can be improved by inserting adhesion layer on gate dielectrics. Adhesion layer was used as polymeric adhesion layer deposited on inorganic gate insulators such as silicon dioxide $(SiO_2)$ and it was formed by vapor deposition polymerization (VDP) instead of spin-coating process. The OTFTs obtained the on/off ratio $of{\sim}10^4$, threshold voltage of 1.8V, subthreshold slop of 2.9 V/decade and field effect mobility about $0.01\;cm^2/Vs$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 전문대학교육위원
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• pp.82-85
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• 2005

Organic EL has been expected to adopt to a new styles of technology that make flat display after Tang & Vanslyke made good electric luminescence device in late 1980s. Their studies based on multi layer structure that consists of emitting layer and carrier transporting layer using proper organic material. In this study, we made multi layer device using $Eu(TTA)_3(phen)$ as a luminescence material by PVD and investigate luminous properties of each device. But oxidization of organic layer by ITO, energy walls in both pole interface, contaminations of ITO surface, importance of protecting membrane, diffusive dimming of light to cathode organic layer, these causes of degradations are common facts of a macromolecule and micromolecule. We think these degradation caused by the impact of heat and electro-chemical factor, bulk effect and interface phenomenon, and raise a question.

• 한국전기전자재료학회논문지
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• 제11권4호
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• pp.334-339
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• 1998

$Bi_2Sr_2CuO_x$(Bi-2201) thin films have been fabricated by atomic layer-by-layer deposition using ion beam sputtering (IBS) method. During the deposition, 14 wt%-ozone/oxygen mixture gas of typical pressure of $5.0\times10^{-5}$ Torr is supplied with ultraviolent light irradiation for oxidation. XRD and RHEED investigations reveal that a buffer layer with compositions different from Bi-2201 is formed at the early deposition stage of less than 10 units cell and then Bi-2201 oriented along the c-axis is grown.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.110-113
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• 2002

Organic EL has been expected to adopt to a new styles of technology that make flat display after Tang & Vanslyke made good electric luminescence device in late 1980s. Their studies based on multi layer structure that consists of emitting layer and carrier transporting layer using proper organic material. In this study. we made multi layer device using $Eu(TTA)_3(phen)$ as a luminescence material by PVD and investigate luminous properties of each device. But oxidization of organic layer by ITO. energy walls in both pole interface. contaminations of ITO surface, importance of protecting membrane, diffusive dimming of light to cathode organic layer. these causes of degradations are common facts of a macromolecule and micromolecule. We think these degradation caused by the impact of heat and electro-chemical factor, bulk effect and interface phenomenon. and raise a question.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.97-100
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• 2000

Bi$_2$Sr$_2$CuO$\sub$x/(Bi(2201)) thin films are fabricated by atomic layer by layer deposition using ion beam sputtering(IBS) method. During the deposition, 10 %-ozone/oxygen mixture gas of typical 5.0 ${\times}$ 10$\^$-5/. Torr is applied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then c-axis oriented Bi(2201) is grown.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.268-271
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• 2005

Etch resistance of mask layer on silicon substrate modified by AFM-based Tribo-Nanolithography (TNL) in Aqueous Solution in an aqueous solution was demonstrated. n consists or sequential processes, nano-scratching and wet chemical etching. The simple scratching can form a mask layer on the silicon substrate, which acting as an etching mask. For TNL, a specially designed cantilever with diamond tip, allowing the formation of mask layer on silicon substrate easily by a simple scratching process, has been applied instead of conventional silicon cantilever fur scanning. This study demonstrates how the TNL parameters can affect the etch resistance of mask layer, hence introducing a new process of AFM-based maskless nanolithography in aqueous solution.